Lock, key blank, and key of a hierarchical lock system

ABSTRACT

A lock system includes keys, key blanks, keyways, and lock cylinders, and the keys or key blanks have opposite sides formed with grooves for cooperating with a conforming keyway. More particularly, the sides of the key or key blank have a portion grooved for registration, another portion grooved for top-level hierarchical master keying, and two other portions, one on each side of the blade, for further master key variations and different combinations. One of the two further sections being curvilinear and the other rectangular or angular cuts. The conforming keyway of the lock includes ridges and grooves corresponding to the grooves and ridges, respectively, of the key or key blank. Instruments other than keys or key blanks may be used to enter the grooves and ridges of the keyway to operate the lock without the use of a precisely configured key.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/694,097 (attorney docket 1233-527), filed Mar. 30, 2007, thedisclosure of which is hereby incorporated by reference.

FIELD OF THE INVENTION

This invention relates to improvements in keys, key blanks, keyways, andlock cylinders, particularly with regard to defining the profiles ofkeys, key blanks, and keyways using the shapes of ridges or grooves in agenerally flat rectangular key blade profile. The shape of the key blankand key, of course, determines the shape of the keyway in a lockcylinder plug.

BACKGROUND AND PRIOR ART

The lock cylinders art is requiring higher and higher security and thereis a need in the art for the development of a shape or profile of across section of key and corresponding shape of the keyway in thecylinder plug to accommodate a hierarchical lock providing highsecurity. The shape of the keyway is the first barrier that rejects orfilters an unauthorized key in attempt to operate the lock cylinder.

There is only a finite space in a lock cylinder plug that can beoccupied by the key and that space must be structured to allow for themaximum number of unique keyway shapes to be able to develop locksystems of adequate size. In large modern lock systems it is usual toarrange the structure of the keyways in a manner so that a least threelevels of a hierarchical system can be provided, with one master keyblank at the top level of the system, some sub-master key blanks at amedium level and several change key blanks at the lowest level of thehierarchical system. A new key section design must be different fromprior key sections so that the key blanks can be controlled by themanufacturer and the end user can benefit from the security offered bythe exclusivity of this key control via the key blanks.

Unique key profile shapes provide for additional protection againstunauthorized key copying. Most key blanks of the generally flatrectangular key profiles are manufactured with single pass formedmilling cutters that shape the side of the key blank. The axis ofrotation of the cutter is held parallel to the side of the blade. Keysusing an undercut groove profile require additional form cutting onspecially designed machines that are usually not available at commercialduplicator operations and thus the blanks are more difficult to copy orcounterfeit.

Early in the development of lock cylinders, it became apparent thatthere were specific parameters that affected the size of the lockcylinder systems that could be developed and that there were many designfactors that influenced the wear of the key and the cylinder and thusthe longevity of the system. Key blanks were designed with theseparameters in mind. Representative examples of the prior art include thefollowing:

In U.S. Pat. No. 0,263,244, Taylor discloses a key blank design thatoffers an economically simple solution to the problem of having a keythat moves too freely in the keyhole. This offers a very minimal keywayshape in the plug and key profile in the blank.

In U.S. Pat. No. 0,420,174, Taylor teaches a unique but limited masterkeying technique that uses a Y shaped key section in a plug that allowstwo differently shaped key profiles to contact their own areas of thenon rotating tumbler pins.

In U.S. Pat. No. 0,567,305, Donavan discloses a method of expanding thenumber of key sections, thus increasing the available size of locksystems, by dividing the key blank height into various areas and usingconsistent warding techniques at these locations to develop hierarchicalkeyways or key profiles. This increases the system size of pin tumblercylinders. The bittings of one key can be repeated on a different keyblank, configured with a different key profile, and the cylinders intowhich these individual keys fit can also be operated by a higher levelkey designed to insert into both of the keyways.

In U.S. Pat. No. 0,608,069, Noack discloses an arrangement of keysection warding that provides improved wear on the key and the keycontact area on the tip of the locking pins. In addition it provides anarrow cross sectional width under the bitting area, thus making itdifficult to manipulate pick tools under the tumbler pins.

In U.S. Pat. No. 3,499,304, M. Noujoks teaches a method of designing keysection warding where both faces of the keys are provided withalternating ridges and grooves. It utilizes a master key blank that hasall the grooves of the series but not the ridges, while the key blanksof a lower hierarchical level have varying ridges.

In U.S. Pat. Nos. 4,168,617 and 4,368,629, Prunbauer discloses moremethods of designing key section warding where the master key will fitinto the subordinate keyways but the lower keys will not fit into themaster keyways. In one embodiment, the ridges and grooves defining thekey section are of a rectangular cross-section shape, and the outwardlyprojecting variable ridge on the subordinate key extends laterallybeyond any of the other variable ridges. The subordinate key is thickerat its further ridge than the master key is at any location. In anotherembodiment the master key is formed of a zigzag shape, that is with itsopposite sides formed of a plurality of planer facets each of which issubstantially parallel to a respective planer facet on the other side.

In U.S. Pat. No. 4,416,128, Steinbrink teaches another unique method ofdesigning key sections where the longitudinal grooves on both sides ofthe key blank are formed with bottom faces that lay substantially alongthe arc of a circle.

In U.S. Pat. No. 4,653,298, Tietz discloses a method of designing masterkey section warding that incorporates an invariable or family profilenear the bitting area on the blank, and the variations defining theindividual key sections are located near the spline or bottom edge ofthe blank. Additionally there are at least two profile formations thatcross a center line in the key blank, one ridge is extending beyond thesurface of the blank, and the variations are made with longitudinalgrooves having rectangular cross sections.

In U.S. Pat. No. 4,683,740, Errani illustrates a key section design thathas a undercut groove shape making it very difficult to manipulate apick tool in the keyway of the plug. The undercut groove is formed bymeans of cutters having their rotational axis inclined in relation tothe sides of the key blank.

In U.S. Pat. Nos. 5,715,717 and 5,809,816, Widen teaches some veryspecific methods of designing key sections using a three sided undercutgroove located closest to the bottom edge of the key blank and extendinginwardly inclined towards the bottom of the key blank, or using anundercut groove with a substantially flat surface which is inclinedtowards the groove bottom surface.

In U.S. Pat. No. 6,145,357, Stefanescu teaches a method of designingmaster key section warding that utilizes a key blank with a T-shapedcross sectional area with all the profile ribs having specificcurvilinear cross sectional contours, with rounded front and flankportions.

In U.S. Pat. No. 6,851,292, Kruhn discloses a method of designing lockand key warding that incorporates specific perpendicular groove surfaceson one side of the key section, and slanting surfaces on the other sidethat are positioned in a relationship designed to trap, or limit themotion of a picking tool inserted into the key way.

While the prior art has developed usable key sections, they fail tomaximize the area of the plug and do not allow for the development ofmany large master keying systems.

SUMMARY OF THE INVENTION

This invention provides specific parameters for key section profiles andthe corresponding keyways in a cylinder plug that allows for thedevelopment of many exclusive and non-interchangeable hierarchicalmaster key systems. In order to accomplish this, the keyway andconforming key blade are considered separately for three verticalsections from the bottom edge of the keyway and blade up to the top edgeof the blade. Each of the three sections is contoured or formed withspecific variations of ridges and grooves that establish the lock's andkey blank's positions within a hierarchical system or systems. Thefirst, bottommost section of the blade has a registry groove for thepositioning of any secondary side milling operations used in themanufacture of the blank, and the keyway has a conforming ridge in itsbottommost section. This registry groove in the blade also allows forexact positioning of the blank in a key cutting or bitting machine. Asecond vertical section of the blade has at least one undercutlongitudinal groove on at least one side of the blade, and the keywayhas a conforming ridge or ridges in its second vertical section. Thelocation and shape of the undercut groove in the second section of theblade determines the primary family of the hierarchical system. Thethird section of the blade, just below the bitting surface, may bedivided into two sides. One of these sides has a variation of the keysection profile determined by using longitudinal grooves of curvedshaped forms that are shifted up and down the side of the blade tocreate the necessary variations. The position and curved form of theprofiles on this side determines the secondary and subgroups in thefamily of the hierarchical system. On the other side of the third, ortopmost section, of the blade, the variations in the key sectionprofiles are determined by using longitudinal grooves havingsubstantially rectangular or straight angular cross sections that varyin depth into the side of the blade. The position and depth of theangular profiles on this third section determine the individual locationin the subgroup in the hierarchical system. The third section of thekeyway has conforming curved ridges and grooves on one side thereof andconforming straight angular or rectangular ridges on the opposite sidethereof.

By using these different but specific warding techniques at definedsections and on different sides of the blade it is possible to develop astructured system to allow the maximum number of new and unique keyprofile shapes. Additionally, by reversing the warding structure fromside to side of the blade within different sections, it is possible tosignificantly increase the already large number of non-interchangeablekey systems available, each providing adequate system size for thedemands of modern security cylinder users.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a prospective view of a key blank of this invention.

FIG. 2 is a cross-sectional view taken along line a-a of FIG. 1 andenlarged.

FIGS. 3 through 9 are cross-sectional views of other key configurationson the sides of the key blanks of this invention that illustrate thefeatures of this invention.

FIG. 10 is an illustrative diagram of a simple three level hierarchicalstructure of keyways.

FIG. 11 a is a side view of a key inserted into a lock cylinder.

FIG. 11 b is a cross-section along the line A-A of FIG. 11 a.

FIG. 11 c is an end view of the lock cylinder of FIG. 11 b, without thekey inserted into the keyway.

FIG. 12 a is a cross-section of a key and keyway along the line A-A inFIG. 11 a, showing a different key and keyway than what is shown in FIG.11 b.

FIG. 12 b is an end view of the lock cylinder of FIG. 12 a, without thekey inserted into the keyway.

FIG. 13 a is a cross-section of a key and keyway along the line A-A inFIG. 11 a, showing a different key and keyway than what is shown inFIGS. 11 b and 12 a.

FIG. 13 b is an end view of the lock cylinder of FIG. 13 a, without thekey inserted into the keyway.

FIG. 14 a is a cross-section of a key and keyway along the line A-A inFIG. 11 a, wherein the keyway is the same keyway shown in FIGS. 11 b and11 c, and the key is a master key.

FIG. 14 b is an end view of the keyway of FIG. 14 a with an instrumentinserted into the keyway for bypassing the profiles of the keyway.

FIG. 15 a is a cross-section of a key and keyway along the line A-A inFIG. 11 a, wherein the keyway is the same keyway shown in FIGS. 12 a and12 b, and the key is the master key shown in FIG. 14 a.

FIG. 15 b is an end view of the keyway of FIG. 15 a with an instrumentinserted into the keyway for bypassing the profiles of the keyway.

FIG. 16 a is a cross-section of a key and keyway along the line A-A inFIG. 11 a, wherein the keyway is the same keyway shown in FIGS. 13 a and13 b, and the key is the master key shown in FIGS. 14 a and 15 a.

FIG. 16 b is an end view of the keyway of FIG. 16 a with an instrumentinserted into the keyway for bypassing the profiles of the keyway.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a prospective view of a key blank according to thisinvention. The key blank has a head or bow 1 for holding and turning thekey and a blade 2 for inserting into a keyway of a lock cylinder. Thekeyway of the lock cylinder has a profile matching the profile of thekey blade. The key blade has a top surface 3 into which key bittings(not shown) are cut to position elements such as pin tumblers in a lockcylinder as is well known in the art, see for example the patent toMedeco Security Locks U.S. Pat. No. 5,419,168. The blank has a bottomsurface 4 and an end tip 5. The end tip 5 may have a stop or otherconfiguration; see for example U.S. Pat. No. 1,679,558.

The cross section of the key blank in one configuration is shown in FIG.2. FIG. 2 shows the top of the key blank blade 3 and the bottom of thekey blank blade 4 and as shown in phantom lines three differentsections. Section A, B, C and C′. As shown, Section A is adjacent to thebottom of the blade, Section C and C′ are adjacent to the top of theblade and Section B is in between Section A and Section C and C′.

Section A contains a groove 6 extending the length of the blade forregistry purposes. When a key blank is being cut with bittings ormachined for other grooves, registry groove 6 is used to provide alocation for further operations relative to such groove.

In Section B there is an undercut groove 7 also extending the length ofthe blade. The undercut groove may be used to provide a first level inthe hierarchical scheme for hierarchical master keying.

The area above the undercut groove is divided into the two sides C andC′ and the shapes and configurations of the grooves and ridges extendingalong these two sides are established by distinctly differentparameters. The shapes in Section C are determined by a base curvilinearshape 110 on which is overlaid a number of partial circular curves 121,122, 123, 124, 125 and 126. These curves are all centered along thebaseline 110. The curves can project either outwardly as convex ridgesor inwardly as concave grooves from the baseline creating either curvedlongitudinal ridges or curved longitudinal grooves along the side of theblank of Section C and below the top surface 3. Similar families ofcurved shapes can be determined by variations in the base curvilinearshape 110, i.e., a different curvilinear shape 110 can function as acenter line for the various circular curves. Subgroups of thesesecondary families may be predetermined by the presence of either curvedridges, e.g., 122, 124, 125, or curved grooves, e.g., 121, 123, 126, andalso by moving the base curvilinear shape 110 either up or down the sideof the blank in relation to the registry groove 6 in Section A.

The shapes of the side of the key blade in Section C′ are determined byproviding rectangular sections such as 134′ and straight angular shapessuch as 131, 132′ and 133 and by varying the depths of these shapes intothe side of the blank. There are a large number of other locations toprovide grooves in Section C′ on this side of the blank, for exampleareas 135″, 136″ and 137″. The size of the grooves and the depths of thegrooves that are formed in Section C′ on this side of the blankdetermine the individual position of the key cut from the key blank inthe family hierarchical structure.

FIG. 3 shows the same cross-sectional view of the key blank butillustrates the base curve 110 shifted vertically in relation toregistry groove 6 to produce a profile 10 in Section C on one side ofthe blade. The rectangular and straight angular shapes in Section C′ onthe other side of the blade has variations, as compared to the key blankof FIG. 2, which define profile 50.

FIG. 4 illustrates another key blank variation in which the base curve110 is positioned at a different height in relation to the registrygroove 6 for cutting the area on the side in Section C producing aprofile indicated at 11. The other side of the key blank in FIG. 4 inSection C′ has a profile 50 showing the differences in cutting groovesand producing ridges.

FIG. 5 is a further cross-sectional view of the key blank illustratingthe base curve 110 producing profile 12 on Section C of the key blankand profile 50 on the other side in Section C′ of the key blank. Profile12 differs from profile 10 in FIG. 3 and profile 11 in FIG. 4 in thatthe base curve 110 is positioned at a different height relative to theregistry groove 6.

FIG. 6 is a cross-sectional view of the key blank illustrating a profile10 in Section C and profile 51 in Section C′. Profile 51 differs fromprofile 50 in that groove 132 projects deeper into the side of the blankthan groove 132′ of FIG. 3.

FIG. 7 is a cross-sectional view of a key blank illustrating profile 10on Section C of the key blank and profile 62 on the other side inSection C′. Profile 62 differs in that groove 141 projects into the sideof the blank at a different straight angular shape than groove 131 inFIG. 2.

FIG. 8 is a further illustration of a cross-sectional view of a keyblank illustrating a profile 23 in one side of the bitting area of theblade in Section C and profile 71 on the other side of the blade inSection C′. In Section C the base curve 110 is the same as shown in FIG.2, however the curved groove 123 is changed to a curved ridge 123′ andthe curved ridge 122 is changed to a curved groove 122′. These changesproduce a different sub-grouping of the secondary families of the keyblank hierarchical structure. In Section C′ of the blank in FIG. 8 thereis no groove in the area 132″ and there is a straight angular groove135. The straight angular grooves 131, 133 and 135 determine theindividual position of the blank in the hierarchical structure.

FIG. 9 is a cross-sectional view of another variation of the key blankshowing profile 31 in Section C and profile 81 in Section C′. Base curve210 of profile 31 determines the location of partial circular curves221-227 that extend as curve grooves 224 or curve ridges 221, 222, 223,225, 226, 227 along the length of the key blade. Secondary families ofthe curved shapes are determined by variations in the base curvilinearshape. The subgroups of these secondary families are determined by thepresence of either curved ridges or curved grooves and by the positionof the base curvilinear shape up or down the side of the blank inrelation to the registry groove 6 in Section A. In profile 81 there areonly two cut grooves 151 and 153 showing further possible variations.

FIG. 10 is an illustrative diagram of a simple three-level hierarchicalstructure of keyways. A key blank that is configured to fit exactly inthe top most key section 1000 is structured to also fit in all of thesubordinate keyways. A key blank that is configured to fit exactly inone of the secondary level keyways, e.g., 1300, will also fit into allof the subordinate keyways 1310, 1320, 1330 of secondary level keyway1300, but not into any of the third level keyways 1110, 1120, 1130 ofsecondary keyway 1100 or 1210, 1220, 1230 of secondary keyway 1200. Thekeys that will fit in the lowest level of the keyways Level 3 will notfit in any of the higher level keyways. This fit or not fitdetermination is accomplished not by the bitting at the top of the keysas is typical in prior art (although such could be used to furtherprovide hierarchical structure) but, is provided by the groovesextending along the sides of the key blank as described above.

FIG. 11 a shows a cylinder lock 300 embodying aspects of the presentinvention into which a key 330, such as a key described above, isinserted in the keyway. Key 330 includes a bow 332 and a blade 334. Thecylinder lock 300 may be part of a lock assembly further including acylinder housing rotatably supporting the cylinder 300 as well astumbler pins, sliders, and other mechanisms (not shown) for preventingrotation of the cylinder within the cylinder housing until a properlyconfigured key or other instrument is inserted into the keyway tooperate the lock.

FIG. 11 b shows a cross-section of the key blade 334 inserted into thekeyway 302 of the cylinder 300. Key blade 334 has a cross-sectionsimilar to that shown in FIG. 9, although key blades havingcross-sections such as those shown in FIGS. 2-8 may also be used. Asdescribed above, the key blade 334 includes a first section near abottom edge 335 of the blade having a groove 336 formed longitudinallyalong at least a portion of the blade 334. Groove 336, as describedabove, may be provided for registry purposes. A second section of theblade 334 includes a groove 338 formed longitudinally along at least aportion of the length of the blade. A third section extending to the topedge 337 of the blade 334 includes, on one side, straight angulargrooves 340, 344 extending longitudinally along at least a portion ofthe blade and, on the opposite side, curved grooves and ridges 342, 346formed longitudinally along at least a portion of the length of theblade. As described above, in the preferred embodiment, one side of thethird section of blade includes only straight, angular, or rectangulargrooves while the opposite side includes only curved grooves and ridges.

FIG. 11 c shows an end view of the cylinder 300 without the key blade334 inserted therein. The cylinder 300 includes the keyway 302 having anopen bottom end 304 and a closed top end 306. A first section of thekeyway 302, adjacent the bottom end 304, includes a ridge 308 conformingto the groove 336 formed in the first section of the blade 334. A secondsection of keyway 302 includes a ridge 310 conforming to groove 338formed in the second section of the blade 334. The third section ofkeyway 302, extending to the top end 306 of the keyway, includes, on oneside thereof, ridges 312, 316 conforming to grooves 340, 344,respectively, formed on one side of the third section of the blade 334and, on the opposite side of the keyway, ridges 314 and grooves 318conforming to the grooves 342 and ridges 346, respectively, formed onthe opposite side of the third section of the blade 334. In a preferredembodiment, ridges 312 and 316 formed on one side of the third sectionof the keyway 302 have only a straight angular shape (as shown) or astraight rectangular shape. The grooves 318 and ridges 314 formed on theopposite side of the keyway 302 in the third section have only curvedshapes.

FIGS. 12 a and 12 b show an end view of a cylinder 300′ having a keyway302′. FIG. 12 a shows the cylinder 300′ with a key blade 334′ insertedinto the keyway 302′. The key blade 334′ is substantially identical tothe key blade 334 shown in FIG. 11 b, except that the groove 340′ formedin the third section of the key blade 334′ has a slightly higherposition relative to the bottom edge 335 than the groove 340 formed inthe key blade 334. Similarly, the ridge 312′ extending into the keyway302′ conforms to the groove 340′ formed in the third section of theblade 334′ and is positioned higher along the keyway 302′ than the ridge312 of the keyway 302 shown in FIG. 11 c.

FIGS. 13 a and 13 b show an end view of a cylinder 300″ having a keyway302″. FIG. 13 a shows the cylinder 300″ with a key blade 334″ insertedinto the keyway 302″. The key blade 334″ is substantially identical tothe key blade 334 shown in FIG. 11 b and the key blade 334′ shown inFIG. 12 a, except that the groove 340″ formed in the third section ofthe key blade 334″ has a slightly higher position relative to the bottomedge 335 than the groove 340′ formed in the key blade 334′ and thegroove 340 formed in the key blade 334. Similarly, the ridge 312″extending into the keyway 302″ conforms to the groove 340″ formed in thethird section of the blade 334″ and is positioned higher along thekeyway 302″ than the ridge 312 of the keyway 302 shown in FIG. 11 c orthe ridge 312′ of the keyway 302′ shown in FIG. 12 b.

FIG. 14 a shows the cylinder 300 (as shown in FIG. 11 b). As describedabove and shown in FIG. 11 c, keyway 302 of cylinder 300 includes afirst ridge 308 in the first section near the bottom 304 of the keyway,a ridge 310 in a second section of the keyway, and in a third section ofthe keyway extending to the top end 306, ridges 312 and 316 formed onone side of the keyway and curved grooves 318 and ridges 314 formed onthe opposite side of the third section of the keyway. FIG. 14 a shows akey blade 350 inserted into the keyway 302. Key blade 350 is essentiallyidentical to key blade 334 shown in FIG. 11 b and includes a groove 336in a first section, a groove 338 in a second section, groove 334 formedin one side of a third section of the blade and grooves 342 and ridges346 formed in the opposite side of the third section of the blade. Blade350 differs from blade 334 in that, instead of having a groove 340 inthe third section conforming to ridge 312 of the keyway 302, key blade350 includes an enlarged groove 352 that accommodates the ridge 312 withexcess room to spare.

FIG. 15 a shows the key blade 350 inserted into the keyway 302′ ofcylinder 300′, and FIG. 16 a shows the key blade 350 inserted into thekeyway 302″ of cylinder 300″. As can be seen in the figures, theenlarged groove 352 formed in the key blade 350 accommodates all of theridges 312, 312′, 312″. Accordingly, key blade 350 is a master key bladethat will operate any of the cylinders 300, 300′, 300″.

A top edge of the blades 334 and 350 may have biting formed therein forpositioning tumblers within the cylinder for operating the lock.

FIGS. 14 b, 15 b, and 16 b show lock cylinders 300, 300′, 300″,respectively, with a lock bypassing instrument 360 inserted into thekeyway of each of the cylinders. More specifically, the instrument 360includes a blade-like projection adapted to be inserted into the keyway,wherein the projection is sufficiently thin to fit into the keywaysbetween the ridges of the keyway. The instrument 360 may have otherfeatures formed therein, such as biting for positioning tumbler pins anda side projection for operating a slider within the keyway. Instrument360 may thus be inserted into the keyway 302, 302′, 302″ and rotated tooperate cylinder 300, 300′, 300″, respectively. Thus, the instrument 360may be used to illicitly bypass the security provided by the uniquecombination of grooves and ridges formed in the keyway which is intendedto be opened only by a properly conforming key having conforming groovesand ridges. The illustrated embodiment is exemplary. The instrument usedto open the lock may take forms different from that shown in FIGS. 14 b,15 b, and 16 b and may comprise two or more pieces used in conjunctionto open the lock as opposed to the single integrally-formed device(instrument 360) shown.

Further variations and modifications of this invention will be apparentto those with ordinary skill in the art of keys and master keying formechanical locks.

1. A lock system comprising: one or more keys including a generallyflat-sided blade, said blade having a top edge, a bottom edge, andopposite sides for receiving grooves and ridges which define across-sectional shape of the blade, wherein the blade is divided intothree or more sections between the bottom edge and the top edge, andwherein the sections comprise: a first section having a registry groovefor registering the key blade by holding the key blade in a referenceposition during machining of the blade; a second section having agroove; and a third section having on a first side thereof only curvedlongitudinal grooves and ridges both defining a curvilinear profile, andon a second side thereof grooves with only substantially rectangular orstraight angular shapes; and one or more locks having a keyway forreceiving the key blade of said key, said blade being constructed andarranged to operate said lock, and wherein said keyway is divided intothree or more sections along its height, said sections comprising: afirst section having a ridge conforming to the registry groove of thefirst section of said blade; a second section having a ridge conformingto the groove of the second section of said blade; and a third sectionhaving on a first side thereof only curved ridges and grooves conformingto the curved grooves and ridges, respectively, of the first side of thethird section of said blade, and on a second side thereof ridges withonly substantially rectangular or straight angular shapes conforming tothe grooves of the second side of the third section of said blade. 2.The lock system of claim 1, wherein the three sections of the key bladeare adjacent to one another, the first section starting at the bottomedge of the key blade and extending upwardly, the second sectionadjacent the first section and in the middle of the key blade, and thethird section between the second section and the top edge of the keyblade.
 3. The lock system of claim 1, comprising two or more keys,wherein at least one groove or ridge in at least one section of theblade of one key is shifted up or down relative to a bottom edge of thekey blade compared to the position of a similar configuration on theother blade to create variations in key blanks within a hierarchicallock system.
 4. The lock system of claim 1, comprising two or more keys,wherein the substantially rectangular or straight angular shapes formedin the third section of one blade are of different depths and differentangles as compared to the other blade to create further variations inkey blade within a hierarchical lock system.
 5. The lock system of claim1, wherein the groove formed in the second section is an undercut grooveextending along a length of the blade.
 6. The lock system of claim 1,comprising two or more keys, wherein at least one groove in at least onesection of the blade of one key is shifted up or down relative to abottom edge of the key blade compared to the position of a similargroove on the other blade to create variations in key blanks within ahierarchical lock system, said system further comprising at least onelock having a keyway conforming to each of said two or more keys.
 7. Thelock system of claim 1, further comprising a master key conforming toall keyways of the lock system.
 8. A lock system comprising: a lockhaving a keyway for receiving a key blade of a key, and wherein saidkeyway is divided into three or more sections along its height, saidsections comprising: a first section having a ridge projecting into thekeyway and conforming to a registry groove of a key blade; a secondsection having a ridge projecting into the keyway and configured todefine a primary family of the lock system; and a third section havingon a first side thereof only curved ridges and grooves and on a secondside thereof ridges projecting into the keyway with only substantiallyrectangular or straight angular shapes; and a key including a generallyflat-sided blade, said blade having a top edge, a bottom edge, andopposite sides, said blade being configured to be inserted into saidkeyway of said lock and to enable a user to operate said lock with saidkey.
 9. The lock system of claim 8, wherein said key blade is dividedinto three or more sections between the bottom edge and the top edge,and wherein the sections comprise: a first section having a registrygroove conforming to the ridge formed in the first section of the keywayand for registering the key blade by holding the key blade in areference position during machining of the blade; a second sectionhaving a groove conforming to the ridge formed in the second section ofthe keyway; and a third section having on a first side thereof onlycurved longitudinal grooves and ridges both conforming to the ridges andgrooves, respectively, of the first side of the third section of thekeyway, and on a second side thereof grooves with only substantiallyrectangular or straight angular shapes and conforming to the ridges ofthe second side of the third section of the keyway.
 10. A method foroperating a lock comprising: providing a lock having a keyway forreceiving a key blade of a key, the keyway being divided into three ormore sections along its height, the sections comprising: a first sectionhaving a ridge projecting into the keyway and conforming to a registrygroove of a key blade; a second section having a ridge projecting intothe keyway and configured to define a primary family of the lock system;and a third section having on a first side thereof only curved ridgesand grooves and on a second side thereof ridges projecting into thekeyway with only substantially rectangular or straight angular shapes;and providing an instrument including at least a portion thereofconfigured to be inserted into said keyway of said lock and to enable auser to operate said lock with the instrument.
 11. The method of claim10, wherein the portion of the instrument configured to be inserted intothe keyway comprises a top edge, a bottom edge, and opposite sides forreceiving grooves and ridges which define a cross-sectional shape of theportion and is divided into three sections between the bottom edge andthe top edge, and wherein the sections comprise: a first section havinga groove conforming to the ridge of the first section of the keyway, asecond section having a groove conforming to the ridge of the secondsection of the keyway; and a third section including a first side havingonly curved ridges and grooves conforming to the curved grooves andridges, respectively, of the first side of the third section the keyway,and a second side having grooves with only substantially rectangular orstraight angular shapes conforming to the ridges of the second side ofthe third section of the keyway.
 12. The method of claim 10, wherein theportion of the instrument configured to be inserted into the keyway issufficiently thin so as to fit into the keyway between the ridges of thekeyway.
 13. A method for operating a lock including a cylinder with akeyway configured to receive a conforming key blade that is divided intothree or more sections between a bottom edge and a top edge thereof, thesections including a first section having a registry groove forregistering the conforming key blade by holding the blade in a referenceposition during machining, a second section having a groove, and a thirdsection having on a first side thereof only curved longitudinal groovesand ridges both defining a curvilinear profile and on a second sidethereof grooves with only substantially rectangular or straight angularshapes, wherein the cylinder is constructed and arranged to be operatedby a user inserting the conforming key blade into the keyway androtating the cylinder, said method comprising: providing an instrumentincluding at least a portion thereof configured to be inserted into thekeyway of the lock and to enable a user to operate the lock with theinstrument; inserting the instrument into the keyway, wherein the keywayis divided into three or more sections along its height, including afirst section having a ridge conforming to the registry groove of thefirst section of the conforming key blade, a second section having aridge conforming to the groove of the second section of the blade; and athird section including a first side having only curved ridges andgrooves conforming to the curved grooves and ridges, respectively, ofthe first side of the third section of the blade and a second sidethereof having ridges with only substantially rectangular or straightangular shapes conforming to the grooves of the second side of the thirdsection of the blade; and manipulating the instrument to operate thecylinder of the lock.
 14. The method of claim 13, wherein the portion ofthe instrument configured to be inserted into the keyway comprises a topedge, a bottom edge, and opposite sides for receiving grooves and ridgeswhich define a cross-sectional shape of the portion and is divided intothree sections between the bottom edge and the top edge, and wherein thesections comprise: a first section having a groove conforming to theridge of the first section of the keyway, a second section having agroove conforming to the ridge of the second section of the keyway; anda third section including a first side having only curved ridges andgrooves conforming to the curved grooves and ridges, respectively, ofthe first side of the third section the keyway, and a second side havinggrooves with only substantially rectangular or straight angular shapesconforming to the ridges of the second side of the third section of thekeyway.
 15. The method of claim 13, wherein the portion of theinstrument configured to be inserted into the keyway is sufficientlythin so as to fit into the keyway between the ridges of the keyway. 16.The method of claim 13, wherein the instrument comprises a single,integrally formed device.